Rats susceptible to anhedonia have more serotonin neurons in the ventral dorsal raphe nucleus. However, activating neurons in the central amygdala reduced the serotonin signaling and lowered the effects of social stress.
Researchers identify an interspecies correlation between hair cortisol concentrations in humans and dogs during summer and winter months. The cortisol levels were not affected by the amount of activity the dog had during these periods. The study reveals a seasonal effect in higher cortisol levels between humans and animals, and human personality traits significantly affected the dog's level of stress. Findings suggest that dogs often mirror the stress levels of their owners.
Chronic social stress in mice induces the expression of virulent genes in the gut microbiota. The altered microbiota increases the presence of effector T helper cells in the lymph nodes and induces myelin autoreactive cells. Exposure to chronic stress, therefore, may increase the risk of developing autoimmune diseases for some individuals with a susceptibility.
In mice, social stress can increase risk factors for cardiovascular disease and shorten life span, researchers report.
Using three different training models, researchers report mental training, mindfulness and meditation can induce structural brain plasticity and reduce social stress.
Findings about how early life social stress affect brain connections in mice may have implications for treating human psychiatric illnesses.
Researchers explore how stress can influence our cognitive performance.